Processing device and method

Abstract

To provide a processing device and a method capable of reducing a downtime of the processing device and suppressing vibration when processing and inspecting a workpiece.SOLUTION: A processing device (10, 10A, 10B, 10C) includes a plurality of stages (ST) configured to be movable independently of each other in a first direction, at least one counterweight (CW1 to CW4) configured to be movable in the first direction, and counterweight control means (50, 58) for moving at least one counterweight so as to suppress vibrations generated by movement of one stage or the other stage.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a processing apparatus and method, and more particularly to a processing apparatus and method for dicing a workpiece (workpiece) such as a wafer on which semiconductor devices or electronic components are formed. [Background technology]

[0002] There is known a laser processing device (laser dicing device) that irradiates a laser beam along a planned dividing line by focusing the beam inside a wafer such as silicon, thereby forming a laser processing area that serves as a starting point for cutting inside the wafer along the planned dividing line (for example, Patent Document 1). The wafer with the laser processing area formed therein is then divided along the planned dividing line by a dividing process such as expanding or breaking, and separated into individual chips. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-195265 [Patent Document 2] Japanese Patent Application Publication No. 2019-149541 Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, in a laser processing device, processing is performed for each wafer in the following order: processing preparation (wafer loading and alignment) → processing operation → post-processing (inspection and unloading). However, if the above series of processes is repeated for each wafer, the processing takes time, which causes a problem of reduced production efficiency.

[0005] In order to improve the production efficiency of the laser processing device, it is preferable to shorten the overall processing time. Specifically, when shortening the overall processing time, "reducing the processing operation time" and "reducing the processing time other than processing" are performed.

[0006] First, in order to achieve "shortening of the processing operation time", it is necessary to increase the processing speed and acceleration. However, there are the following problems in increasing the processing speed and acceleration. (1) Enlargement of the motor used for relative movement of the wafer or the like (2) High responsiveness of autofocus (3) High output and high repetition frequency of the laser (4) Increase in vibration of the apparatus due to improvement of acceleration Among the above (1) to (4), the responsiveness of the autofocus in (2) may be reduced due to the influence of the vibration of the laser processing apparatus in (4). Therefore, it is difficult to significantly improve the responsiveness of autofocus.

[0007] Next, in order to achieve "shortening of the processing time other than processing", speeding up of the wafer transfer system, improvement of the stage feed speed, optimization of the alignment operation, etc. can be mentioned. However, it is difficult to dramatically shorten the processing time by these methods.

[0008] By the way, while performing processing other than laser processing (for example, inspection), the optical unit (processing apparatus) for laser processing stops. If the downtime of the processing apparatus, which accounts for most of the price of the laser processing apparatus, becomes long, the cost-effectiveness of the laser processing apparatus will decrease.

[0009] When the production efficiency is improved and a large amount of processing can be performed in a short time, inspection of processing defects and the like becomes important. When strictly inspecting processing defects and the like for a large number of products, it is expected that the time required for inspection of the processing state (measurement of internal cracks, etc.) will become long.

[0010] In order to improve the production efficiency of the laser processing apparatus, an apparatus has been proposed in which processing and inspection can be respectively executed on a plurality of stages (wafer tables) (see Patent Document 2).

[0011] In the laser processing apparatus (laser dicing apparatus) described in Patent Document 2, the ratio of the weight of the stage and its driving device to the weight of the laser processing apparatus is high. Therefore, when the stage is transferred, vibration occurs, which affects the accuracy of laser processing and inspection.

[0012] The present invention has been made in view of such circumstances, and an object thereof is to provide a processing apparatus and method capable of shortening the downtime of the processing apparatus when performing processing and inspection of a workpiece and suppressing vibration.

Means for Solving the Problems

[0013] In order to solve the above problems, a processing apparatus according to a first aspect of the present invention includes a plurality of stages configured to be independently movable in a first direction, respectively, a processing means configured to be movable in a second direction orthogonal to the first direction and process a first workpiece held on one of the plurality of stages, an inspection means configured to be movable in the second direction independently of the processing means and inspect a second workpiece held on another of the plurality of stages, at least one counterweight configured to be movable in the first direction, and a counterweight control means for moving at least one counterweight so as to suppress vibration generated by the movement of one stage or the other stage.

[0014] A processing apparatus according to a second aspect of the present invention is, in the first aspect, the counterweight control means moves at least one counterweight in a direction opposite to the moving direction of one stage or the other stage.

[0015] A processing apparatus according to a third aspect of the present invention is, in the first aspect, the counterweight control means moves at least one counterweight in a direction opposite to the moving direction of the stage facing the processing means among one stage or the other stage.

[0016] A fourth aspect of the present invention is a processing apparatus in any of the first to third aspects, wherein the multiple stages include a first stage and a second stage arranged side by side in a second direction, and at least one counterweight includes a first counterweight arranged on the side of the first stage opposite to the side on which the second stage is arranged, and a second counterweight arranged on the side of the second stage opposite to the side on which the first stage is arranged.

[0017] A fifth aspect of the present invention is a processing apparatus according to any one of the first to fourth aspects, wherein the multiple stages include a first stage and a second stage arranged side by side in a second direction, and at least one counterweight includes a third counterweight arranged between the first stage and the second stage.

[0018] A sixth aspect of the present invention is a processing apparatus in any of the first to third aspects, wherein the multiple stages include a first stage and a second stage arranged side by side in a second direction, and the at least one counterweight includes a pair of first stage side counterweights arranged on both sides of the first stage and a pair of second stage side counterweights arranged on both sides of the second stage.

[0019] A processing device according to a seventh aspect of the present invention is the processing device according to any one of the first to sixth aspects, wherein the processing means processes the workpiece with a laser.

[0020] A processing method according to an eighth aspect of the present invention includes the steps of moving a processing means to a position opposite one of the multiple stages, moving an inspection means to a position opposite another of the multiple stages, processing a first workpiece held on one of the stages by the processing means while moving the one stage relative to the processing means, inspecting a second workpiece held on the other stage by the inspection means while moving the other stage relative to the inspection means, and moving at least one counterweight to suppress vibrations generated by movement of the one stage or the other stage. [Effects of the Invention]

[0021] According to the present invention, it is possible to shorten the downtime of a processing apparatus when performing work processing and inspection, and to suppress vibration.

Brief Description of the Drawings

[0022]

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Embodiments for Carrying Out the Invention

[0023] Hereinafter, embodiments of the processing apparatus and method according to the present invention will be described with reference to the accompanying drawings.

[0024] [First Embodiment] (Processing Apparatus) FIGS. 1 to 3 are a plan view, a front view, and a side view, respectively, showing a processing apparatus (laser processing apparatus) according to the first embodiment of the present invention. In the following description, a three-dimensional orthogonal coordinate system will be used.

[0025] As shown in FIGS. 1 to 3, the laser processing apparatus 10 according to the present embodiment includes a first stage 14-1, a second stage 14-2, a processing unit 28, and an inspection unit 30. The laser processing apparatus 10 can perform processing and inspection of a workpiece (wafer) in parallel (for example, simultaneously) on the first stage 14-1 and the second stage 14-2.

[0026] The laser processing apparatus 10 is provided on a base 12 parallel to the horizontal plane (XY plane). The base 12 forms a reference plane of the laser processing apparatus 10.

[0027] The first stage 14-1 and the second stage 14-2 (hereinafter also referred to as the X stage) are arranged side by side in the Y direction (second direction), and are movably attached along the X1 axis and the X2 axis extending in the X direction (first direction), respectively. Here, as a mechanism for moving the first stage 14-1 and the second stage 14-2, for example, a ball screw mechanism including nuts provided on the first stage 14-1 and the second stage 14-2, respectively, and ball screws screwed into the nuts, a linear motor, or a rack and pinion mechanism, etc., can be used to reciprocate the first stage 14-1 and the second stage 14-2 in the X direction, respectively.

[0028] θ stages 16-1 and 16-2 are attached to the first stage 14-1 and the second stage 14-2, respectively. Wafer chucks C1 and C2 are attached to the θ stages 16-1 and 16-2, respectively. The θ stages 16-1 and 16-2 rotate the wafer chucks C1 and C2 around their respective rotation axes (e.g., central axes) (in the θ direction).

[0029] Suction holes for sucking air are formed on the surfaces of the wafer chucks C1 and C2. The wafer chucks C1 and C2 suction-hold the wafers W1 and W2, respectively, that are loaded into the laser processing apparatus 10 as targets for laser processing.

[0030] As described above, the first stage 14-1 and the second stage 14-2 have similar configurations, and therefore, in the following description, the configurations and operations common to both the first stage 14-1 and the second stage 14-2 may be collectively described without sub-numbers.

[0031] A Y base 18 is provided above the base 12. The Y base 18 forms a reference plane along the Y direction. The Y base 18 is supported by a support extending in the Z direction from the base 12. A Y1 axis and a Y2 axis, each extending in the Y direction, are attached to the Y base 18. As shown in FIGS. 2 and 3, the Y1 axis is disposed offset in the +Z direction and +X direction with respect to the Y2 axis.

[0032] A Y-axis moving stage for processing 20 and a Y-axis moving stage for inspection 24 (hereinafter referred to as Y stages 20 and 24) are attached to the Y1 axis and the Y2 axis, respectively.

[0033] A processing unit 28 is attached to the Y stage 20 via a processing Z-axis moving stage (hereinafter referred to as the Z stage) 22. The processing unit (processing means) 28 can be moved in the Y and Z directions by the Y stage 20 and the Z stage 22. For the Y stage 20 and the Z stage 22, it is possible to use mechanisms (for example, a ball screw mechanism, a linear motor, or a rack and pinion mechanism) that can cause the processing unit 28 to move back and forth in a linear manner in the Y and Z directions.

[0034] An inspection unit 30 is attached to the Y stage 24 via an inspection Z-axis moving stage (hereinafter referred to as the Z stage) 26. The inspection unit (inspection means) 30 can be moved in the Y and Z directions by the Y stage 24 and the Z stage 26. The Y stage 24 and the Z stage 26 can be mechanisms (for example, a ball screw mechanism, a linear motor, or a rack and pinion mechanism) that can move the inspection unit 30 back and forth in a linear manner in the Y and Z directions.

[0035] The processing section 28 includes a laser processing optical unit (hereinafter referred to as the processing unit) 28A and an alignment optical unit (hereinafter referred to as the optical unit) 28B. The processing unit 28A and the optical unit 28B are movable as a unit in the Y and Z directions.

[0036] The processing unit 28A includes a laser oscillator and a condenser lens (see Japanese Patent Application Laid-Open No. 2004-111946), and the laser beam output from the laser oscillator is condensed inside the wafer W (W1 or W2) by the condenser lens. As a result, a laser processing area is formed inside the wafer W, which serves as a starting point for cutting the wafer W.

[0037] The optical unit 28B includes an imaging device (e.g., an indium gallium arsenide (InGaAs) photodiode or a charge-coupled device (CCD) image sensor) that captures an image of the wafer W. The control device 50 (see FIG. 4) detects the position of the alignment pattern from the image of the wafer W captured by the optical unit 28B, and controls the X drive unit 54, the θ drive unit 56, the Y drive unit 60, and the Z drive unit 62 to align the processing unit 28A and the wafer W.

[0038] The inspection unit 30 includes an inspection optical unit (hereinafter referred to as an inspection unit) 30A and an alignment optical unit (hereinafter referred to as an optical unit) 30B. The inspection unit 30A and the optical unit 30B are integrally movable in the YZ direction.

[0039] The inspection unit 30A measures the length of a crack extending from the laser processing region. As the inspection unit 30A, for example, the crack detection device described in Japanese Patent Application Laid-Open No. 2017-133997 can be applied.

[0040] The optical unit 30B includes an imaging device (e.g., an indium gallium arsenide (InGaAs) photodiode or a charge-coupled device (CCD) image sensor) that captures an image of the wafer W. The control device 50 detects the position of the alignment pattern from the image of the wafer W captured by the optical unit 30B, and controls the X drive unit 54, the θ drive unit 56, the Y drive unit 64, and the Z drive unit 66 to align the inspection unit 30A and the wafer W.

[0041] In the laser processing apparatus 10 according to the present embodiment, the processing unit 28 is disposed on the +X side of the inspection unit 30 due to the positional relationship between the Y stages 20 and 24, but the present invention is not limited thereto. For example, the inspection unit 30 may be disposed on the +X side of the processing unit 28.

[0042] Counterweights CW1 to CW3 are disposed on the base 12. The counterweights CW1 to CW3 are movable along guide rails G1 to G3, respectively, which extend in the X direction.

[0043] 1, the counterweight CW1, first stage 14-1, counterweight CW3, second stage 14-2, and counterweight CW2 are arranged in this order from the +Y side on the base 12. The counterweights CW1 to CW3 and guide rails G1 to G3 function as a vibration suppression mechanism 58 (see FIGS. 4 to 7) for suppressing vibrations of the laser processing apparatus 10 that occur when the first stage 14-1 and second stage 14-2 are moved along the X1 axis and the X2 axis.

[0044] The weights of the counterweights CW1 to CW3 are adjusted so as to cancel out the rotational moment that occurs when the first stage 14-1 and the second stage 14-2 are moved along the X1 axis and the X2 axis, respectively. The weights of the counterweights CW1 and CW2, which are arranged on the outer side of the first stage 14-1 and the second stage 14-2, and the weight of the counterweight CW3, which is arranged on the inner side of the first stage 14-1 and the second stage 14-2, may be different.

[0045] In addition, the positional relationship (e.g., the distance in the Y direction or the height in the Z direction) between the counterweights CW1 to CW3 and the first stage 14-1 and the second stage 14-2 may be adjusted so as to cancel out the rotational moment that occurs when the first stage 14-1 and the second stage 14-2 are moved.

[0046] (Laser processing equipment control system) FIG. 4 is a block diagram showing a laser processing apparatus according to a first embodiment of the present invention.

[0047] As shown in FIG. 4, the laser processing apparatus 10 according to the present embodiment includes a control device 50, an input / output unit 52, X drive units 54-1 and 54-2, θ drive units 56-1 and 56-2, a vibration control mechanism 58, a Y drive unit 60, a Z drive unit 62, a Y drive unit 64, and a Z drive unit 66.

[0048] The control device 50 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a storage device (e.g., a hard disk, etc.). In the control device 50, various programs such as control programs stored in the ROM are expanded in the RAM, and the programs expanded in the RAM are executed by the CPU, whereby the functions of each part of the laser processing apparatus 10 are realized.

[0049] The input / output unit 52 includes an operation member (e.g., a keyboard, a pointing device, etc.) for receiving an operation input from a user, and a device (e.g., a liquid crystal display) for displaying a GUI (Graphical User Interface) for operating the laser processing apparatus 10.

[0050] The X drive units 54-1 and 54-2 each include a power source (e.g., a motor) for moving the first stage 14-1 and the second stage 14-2 attached to the X1 axis and the X2 axis in the X direction. The X drive units 54-1 and 54-2 are an example of a first drive device.

[0051] The θ drive units 56-1 and 56-2 each include a power source (e.g., a motor) for rotating the wafer chucks C1 and C2 attached to the θ stages 16-1 and 16-2 in the θ direction.

[0052] The Y drive unit 60 includes a power source (e.g., a motor) for moving the processing unit 28 attached to the Y stage 20 in the Y direction via the Z stage 22.

[0053] The Z drive unit 62 includes a power source (for example, a motor) for moving the processing unit 28 attached to the Z stage 22 in the Z direction.

[0054] The Y drive unit 64 includes a power source (for example, a motor) for moving the inspection unit 30 attached to the Y stage 24 in the Y direction via the Z stage 26.

[0055] The Z drive unit 66 includes a power source (for example, a motor) for moving the inspection unit 30 attached to the Z stage 26 in the Y direction.

[0056] The above-mentioned Y drive units 60 and 64 and Z drive units 62 and 66 are an example of a second drive device.

[0057] The vibration suppression mechanism 58 includes a power source (e.g., a motor) for moving the counterweights CW1 to CW3 along the guide rails G1 to G3, respectively. The vibration suppression mechanism 58 controls the direction, amount, speed, and acceleration of movement of the counterweights CW1 to CW3 in accordance with the direction, amount, speed, and acceleration of movement of the first stage 14-1 and the second stage 14-2. This makes it possible to suppress vibrations of the laser processing apparatus 10 that occur when the first stage 14-1 and the second stage 14-2 are moved. Here, the counterweights CW1 to CW3 are examples of first to third counterweights, respectively, and the control device 50 and the vibration suppression mechanism 58 are examples of counterweight control means.

[0058] (Processing method) Next, the control of the vibration suppression mechanism 58 during laser processing will be described with reference to FIGS.

[0059] In the following description, an example will be described in which laser processing and inspection are sequentially performed on wafers W0, W1, W2, W3, ..., W(2i-1), W(2i), ..., where i = 1, 2, 3, .... Wafers W1, W3, ..., W(2i-1), ... are processed in the first stage 14-1, and wafers W0, W2, ..., W(2i), ... are processed in the second stage 14-2. That is, first, wafers W0 and W1 are loaded into the second stage 14-2 and the first stage 14-1, respectively, and laser processing of wafer W0 is performed. Next, inspection of wafer W0 in the second stage 14-2 and laser processing of wafer W1 in the first stage 14-1 are performed in parallel.

[0060] FIG. 5 is a plan view showing the wafer processing and inspection performed on the first and second stages, respectively, and FIG. 6 is a plan view showing the wafer inspection and processing performed on the first and second stages, respectively.

[0061] 5, laser processing is performed on wafer W1 in first stage 14-1, and inspection of wafer W0 after laser processing is performed in second stage 14-2. In this case, first, control device 50 moves the Y-direction positions of processing unit 28 and inspection unit 30 according to the Y-direction positions of first stage 14-1 and second stage 14-2, respectively. That is, control device 50 moves processing unit 28 and inspection unit 30 so as to face first stage 14-1 and second stage 14-2, respectively.

[0062] Furthermore, the control device 50 moves the first stage 14-1 to the +X side and the second stage 14-2 to the -X side according to the X-direction positions of the processing unit 28 and the inspection unit 30. The control device 50 controls the vibration suppression mechanism 58 to move the counterweights CW1 to CW3 so as to cancel out the rotational moment that occurs when the first stage 14-1 and the second stage 14-2 are moved in the X direction.

[0063] 5, while the first stage 14-1 moves to the +X side, the counterweights CW1 and CW3 disposed on either side of the first stage 14-1 move in the opposite direction (to the -X side). Then, the counterweights CW1 to CW3 are operated in accordance with the movements of the first stage 14-1 and the second stage 14-2 during processing and inspection, thereby canceling out the rotational moment of the laser processing apparatus 10.

[0064] Next, the control device 50 performs laser processing on the wafer W1 and inspection of the wafer W0 after laser processing in parallel. Specifically, the control device 50 controls the X drive unit 54-1, the θ drive unit 56-1, the Y drive unit 60, and the Z drive unit 62 to move the first stage 14-1 and the processing unit 28 relatively, while performing laser processing along the planned dividing line of the wafer W1 and forming a laser-processed area. The control device 50 also controls the X drive unit 54-2, the θ drive unit 56-2, the Y drive unit 64, and the Z drive unit 66 to move the second stage 14-2 and the inspection unit 30 relatively, while inspecting the laser-processed area formed on the wafer W0 (measuring the length of a crack).

[0065] Next, after the inspection of wafer W0 is completed, a handler arm (not shown) unloads wafer W0 from laser processing apparatus 10. Then, the next wafer W2 is loaded into laser processing apparatus 10 by a handler arm (not shown), and is placed on wafer chuck C2 and held by suction.

[0066] 6, the wafer W1 after laser processing is inspected on the first stage 14-1, and the wafer W2 is laser processed on the second stage 14-2. In this case, the control device 50 moves the Y-direction positions of the processing unit 28 and the inspection unit 30 according to the Y-direction positions of the second stage 14-2 and the first stage 14-1, respectively.

[0067] Furthermore, the control device 50 moves the first stage 14-1 to the -X side and the second stage 14-2 to the +X side according to the X-direction positions of the processing unit 28 and the inspection unit 30. The control device 50 controls the vibration suppression mechanism 58 to move the counterweights CW1 to CW3 so as to cancel out the rotational moment that occurs when the first stage 14-1 and the second stage 14-2 are moved in the X direction.

[0068] 6, while the second stage 14-2 moves to the +X side, counterweights CW2 and CW3 disposed on either side of the second stage 14-2 are moved in the opposite direction (-X side). Then, the counterweights CW1 to CW3 are operated in accordance with the movements of the first stage 14-1 and the second stage 14-2 during processing and inspection, thereby canceling out the rotational moment of the laser processing apparatus 10. This makes it possible to cancel out the rotational moment of the laser processing apparatus 10.

[0069] Next, control device 50 inspects the laser-processed area formed on wafer W1 by controlling X drive unit 54-1, θ drive unit 56-1, Y drive unit 64, and Z drive unit 66 to move first stage 14-1 relatively to inspection unit 30. Control device 50 also controls X drive unit 54-2, θ drive unit 56-2, Y drive unit 60, and Z drive unit 62 to move second stage 14-2 relatively to processing unit 28, and performs laser processing along the planned dividing line of wafer W2 to form a laser-processed area.

[0070] In this embodiment, when the X stage 14 moves in the -X direction, the counterweights (CW1 to CW3) arranged to sandwich the X stage 14 are moved, but the present invention is not limited to this. It is also possible to move one counterweight that is closest to the moving X stage 14.

[0071] Furthermore, the movement speed or movement acceleration of the counterweights (CW1 to CW3) may be adjusted according to the weight, movement speed or movement acceleration of the moving X stage 14 and the weight of the counterweights (CW1 to CW3). For example, the momentum of the counterweights (CW1 to CW3) may be adjusted according to the momentum of the X stage 14 during movement.

[0072] Furthermore, the counterweights (CW1 to CW3) located on the opposite side (e.g., point symmetric) of the moving X stage 14 with respect to the center or center of gravity in the XY plane of the laser processing apparatus 10 may be configured to be movable in the opposite direction (e.g., point symmetric) to the moving direction of the X stage 14. In this case, the momentum of the counterweights (CW1 to CW3) may be adjusted according to the momentum of the X stage 14 during movement and the distance from the center or center of gravity of the X stage 14 and the counterweights (CW1 to CW3).

[0073] Furthermore, the X stage 14 and the counterweights (CW1 to CW3) may be moved in synchronization with each other, that is, the start and stop timings of the movements of the X stage 14 and the counterweights (CW1 to CW3) may be synchronized.

[0074] Fig. 7 is a timing chart showing the procedure of laser processing according to the first embodiment of the present invention. In Fig. 7, the area surrounded by a dotted line indicates a step using the processing section 28 (processing unit 28A), and the area surrounded by a dashed line indicates a step using the inspection section 30 (inspection unit 30A). In addition, the positional relationship of the configuration of the laser processing apparatus 10 in section P(i-1) shown in Fig. 7 corresponds to Fig. 5, in which processing and inspection are performed on the first stage 14-1 and the second stage 14-2, respectively, and the positional relationship in section P(i) corresponds to Fig. 6, in which inspection and processing are performed on the first stage 14-1 and the second stage 14-2, respectively.

[0075] (Processing in the second stage 14-2: steps S5 to S3) In step S5(2(i-1)), the control device 50 uses the inspection unit 30 to inspect the laser processing area formed on the wafer W(2(i-1)) (inspection step). At this time, the control device 50 moves the counterweights CW2 and CW3 arranged on either side of the second stage 14-2 in accordance with the operation during inspection (operation of the second stage 14-2) to suppress vibration of the laser processing device 10. Then, when the inspection of the wafer W(2(i-1)) is completed, the control device 50 records the inspection results and outputs them via the input / output unit 52.

[0076] Next, the control device 50 releases the wafer W(2(i-1)) from the suction state on the wafer chuck C2, and unloads the wafer W(2(i-1)) from the laser processing device 10 using a handler arm (not shown) (step S6(2(i-1))).

[0077] Next, the control device 50 prepares for processing the wafer W (2i) (steps S1 (2i) to S3 (2i)). First, the control device 50 loads the wafer W (2i) into the laser processing device 10 using a handler arm (not shown) (step S1 (2i)).

[0078] Next, the control device 50 controls the Z drive unit 66 to set the Z-direction height of the inspection unit 30 (step S2(2i)). Then, the control device 50 acquires an image of the wafer W(2i) using the optical unit 30B, detects the position of the alignment pattern, detects the position of the wafer W(2i), and performs alignment (for example, alignment in the θ and Y directions) (step S3(2i)).

[0079] (Processing in the first stage 14-1: Step S4) Meanwhile, the control device 50 performs step S4(2i-1) (processing step) in parallel with steps S5(2(i-1)) to S3(2i). That is, the control device 50 uses the processing unit 28 to perform laser processing on the wafer W(2i-1) held by suction on the first stage 14-1, and forms a laser-processed area along the planned dividing line of the wafer W(2i-1). At this time, the control device 50 moves counterweights CW1 and CW3 arranged on either side of the first stage 14-1 in accordance with the operation during processing (operation of the first stage 14-1) to suppress vibration of the laser processing device 10.

[0080] (Preparation for processing and inspection: Step S10) When the processing of wafer W(2i-1) on first stage 14-1 and preparation for processing wafer W(2i) on second stage 14-2 (steps S1(2i) to S3(2i)) are completed, control device 50 inspects wafer W(2i-1) and prepares for processing wafer W(2i) (step S10(i)). That is, control device 50 controls Y drive unit 60 to move processing unit 28 toward second stage 14-2, and controls Y drive unit 64 to move inspection unit 30 toward first stage 14-1. Control device 50 also controls X drive units 54-1 and 54-2 to move first stage 14-1 and second stage 14-2 in the -X direction and +X direction, respectively.

[0081] (Preparation in the second stage 14-2: Step S10) Next, the control device 50 controls the Z drive unit 62 to set the Z-direction height of the processing unit 28. Then, the control device 50 acquires an image of the wafer W(2i) using the optical unit 28B, detects the position of the alignment pattern, detects the position of the wafer W(2i), and aligns the processing unit 28A with the wafer W(2i) (for example, alignment in the X, θ, Y, and Z directions).

[0082] (Preparation in the first stage 14-1: Step S10) Meanwhile, the control device 50 controls the Z drive unit 66 to set the Z-direction height of the inspection unit 30. Then, the control device 50 acquires an image of the wafer W(2i-1) using the optical unit 30B, detects the position of the alignment pattern, detects the position of the wafer W(2i-1), and aligns the inspection unit 30A with the wafer W(2i-1) (for example, in the X, θ, Y, and Z directions).

[0083] (Processing in the second stage 14-2: Step S4) Next, the control device 50 uses the processing unit 28 to perform laser processing on the wafer W(2i) held by suction on the second stage 14-2, forming a laser processing area along the planned dividing line of the wafer W(2i) (step S4(2i)).

[0084] (Processing in the first stage 14-1: steps S5 to S3) Meanwhile, the control device 50 inspects the laser processed area formed on the wafer W(2i-1) using the inspection unit 30 (step S5(2i-1)). Then, when the inspection of the wafer W(2i-1) is completed, the control device 50 records the inspection results and outputs them via the input / output unit 52.

[0085] Next, the control device 50 unloads the wafer W(2i-1) from the wafer chuck C2 (step S6(2i-1)), loads the wafer W(2i+1) and prepares for processing (steps S1(2i+1) to S3(2i+1)).

[0086] As described above, in this embodiment, steps S1 to S6 and S10 are alternately repeated in the first stage 14-1 and the second stage 14-2. This makes it possible to reduce downtime of the processing unit 28 and the inspection unit 30. Furthermore, by moving the counterweights CW1 to CW3 in accordance with the movement of the first stage 14-1 and the second stage 14-2, it becomes possible to reduce vibrations of the laser processing apparatus 10.

[0087] [Second embodiment] Next, a second embodiment of the present invention will be described with reference to Fig. 8. Fig. 8 is a plan view and a front view showing a laser processing apparatus according to the second embodiment of the present invention. In the following description, the same components as those in the first embodiment will be assigned the same reference numerals and description thereof will be omitted.

[0088] 8, in the laser processing apparatus 10A according to this embodiment, only one counterweight CW3 is disposed between the first stage 14-1 and the second stage 14-2. That is, in the laser processing apparatus 10A according to this embodiment, the first stage 14-1, the counterweight CW3 (guide rail G3), and the second stage 14-2 are disposed in this order from the +Y side.

[0089] The control device 50 operates the counterweight CW3 to suppress vibrations of the laser processing device 10 (X stage 14) that occur due to operations (operations of the X stage 14) during processing or inspection. Specifically, the counterweight CW3 is moved in the opposite direction to the movement direction of the X stage 14. For example, when processing steps and inspection steps are performed in parallel, by staggering the movement timing of the first stage 14-1 and the second stage 14-2, it becomes possible to suppress vibrations generated by the first stage 14-1 and the second stage 14-2 with just one counterweight CW3.

[0090] According to this embodiment, the number of counterweights is reduced to one, so the size and weight of the laser processing apparatus 10A can be reduced compared to the first embodiment. Furthermore, according to this embodiment, the stroke in the Y direction can be shortened.

[0091] [Third embodiment] Next, a third embodiment of the present invention will be described with reference to Fig. 9. Fig. 9 is a plan view and a front view showing a laser processing apparatus according to the third embodiment of the present invention. In the following description, the same components as those in the above embodiments will be denoted by the same reference numerals and description thereof will be omitted.

[0092] 9, in the laser processing apparatus 10B according to this embodiment, two counterweights CW1 and CW2 are arranged on the outer sides of the first stage 14-1 and the second stage 14-2, respectively. That is, in the laser processing apparatus 10B according to this embodiment, the counterweight CW1 (guide rail G1), the first stage 14-1, the second stage 14-2, and the counterweight CW2 (guide rail G2) are arranged in this order from the +Y side.

[0093] The control device 50 operates the counterweights CW1 and CW2 to suppress vibrations of the laser processing apparatus 10 (X stage 14) that occur due to operations (operations of the X stage 14) during processing or inspection. For example, the counterweight CW1 closest to the first stage 14-1 is moved in the direction opposite to the movement direction of the first stage 14-1, and the counterweight CW2 closest to the second stage 14-2 is moved in the direction opposite to the movement direction of the second stage 14-2. Alternatively, the counterweight CW2 on the opposite side of the first stage 14-1 with respect to the center or center of gravity of the laser processing apparatus 10 may be moved in the direction opposite to the movement direction of the first stage 14-1, and the counterweight CW1 on the opposite side of the second stage 14-2 may be moved in the direction opposite to the movement direction of the second stage 14-2.

[0094] According to this embodiment, the number of counterweights is set to two, so the size and weight of the laser processing apparatus 10B can be reduced compared to Embodiment 1. Furthermore, according to this embodiment, the stroke in the Y direction can be shortened.

[0095] [Fourth embodiment] Next, a fourth embodiment of the present invention will be described with reference to Fig. 10. Fig. 10 is a plan view and a front view showing a laser processing apparatus according to the fourth embodiment of the present invention. In the following description, the same components as those in the above embodiments will be denoted by the same reference numerals and description thereof will be omitted.

[0096] 10, in the laser processing apparatus 10C according to this embodiment, two counterweights CW1 and CW2 are disposed on the outer sides of the first stage 14-1 and the second stage 14-2, respectively, and two counterweights CW3 and CW4 are disposed on the inner sides of the first stage 14-1 and the second stage 14-2, respectively. That is, in the laser processing apparatus 10C according to this embodiment, the arrangement is, from the +Y side, counterweight CW1 (guide rail G1), the first stage 14-1, counterweights CW3 and CW4 (guide rails G3 and G4), the second stage 14-2, and counterweight CW2 (guide rail G2). Here, counterweights CW1 and CW3 are an example of a pair of first-stage counterweights disposed on both sides of the first stage 14-1, and counterweights CW2 and CW4 are an example of a pair of second-stage counterweights disposed on both sides of the second stage 14-2.

[0097] The control device 50 operates the counterweights CW1 to CW4 to suppress vibrations of the laser processing device 10 (X stage 14) that occur due to operations (operations of the X stage 14) during processing or inspection. Specifically, the counterweights CW1 and CW3, which are arranged to sandwich the first stage 14-1, are moved in the direction opposite to the movement direction of the first stage 14-1, and the counterweights CW2 and CW4, which are arranged to sandwich the second stage 14-2, are moved in the direction opposite to the movement direction of the second stage 14-2.

[0098] According to this embodiment, two counterweights are arranged on either side of the first stage 14-1 and the second stage 14-2, so that the rotational moment of the laser processing apparatus 10C generated by the operation of the processing unit 28, the inspection unit 30, etc. can be more effectively canceled out, thereby enhancing the vibration damping effect.

[0099] [Example] Next, the vibration damping effect of the laser processing device according to the above embodiment will be described with reference to Fig. 11. Fig. 11 is a graph showing the relationship between the number of counterweights and the displacement of the laser processing device.

[0100] Fig. 11(a) shows the displacement during operation of the laser processing device (comparative example) when no counterweight is provided, Fig. 11(b) corresponds to the case when one counterweight is provided (second embodiment), and Fig. 11(c) corresponds to the case when two counterweights are provided (third embodiment).

[0101] In FIG. 11, the numerical values of the elapsed time and displacement are omitted, but the scales of the elapsed time and displacement are the same in (a) to (c) of FIG.

[0102] As shown in FIG. 11(a), if a counterweight is not provided, the movement of the X stage will cause vibrations in the laser processing device, which will affect the accuracy of laser processing and inspection for processing defects.

[0103] 11(b) and 11(c), when counterweights are provided, the vibrations of the laser processing apparatuses 10A and 10B caused by the movement of the first stage 14-1 and the second stage 14-2 are suppressed. The more counterweights there are, the more the vibration suppression effect can be improved.

[0104] In this embodiment, the movement directions of the first stage 14-1 and the second stage 14-2 are parallel, but the present invention is not limited to this. Even if the movement directions of the first stage 14-1 and the second stage 14-2 are non-parallel, vibration can be suppressed by providing a counterweight and guide rails that can move parallel to the movement directions of the first stage 14-1 and the second stage 14-2.

[0105] In addition, in this embodiment, the laser processing apparatus has been described as having two X stages, but the present invention is not limited to this. Even if three or more X stages are provided, vibration can be suppressed by providing counterweights and guide rails that can move parallel to the movement direction of each X stage.

[0106] Furthermore, in this embodiment, a case has been described in which crack detection is performed as an inspection performed in parallel with processing in a laser processing apparatus equipped with multiple X stages, but the present invention is not limited to this and can also be applied to cases in which inspections other than crack detection are performed in parallel with processing. Furthermore, the inspection in this embodiment is performed on the workpiece W after laser processing, but this embodiment can also be applied to inspection of the workpiece W before laser processing, and can be performed in parallel with processing. Furthermore, the processing in this embodiment is laser processing, but this embodiment can also be applied to cases in which processing other than laser processing (for example, blade dicing) is performed. [Explanation of symbols]

[0107] 10, 10A, 10B, 10C...laser processing device, 12...base, 14-1...first stage, 14-2...second stage, 16-1, 16-2...θ stage, 18...Y base, 20, 24...Y stage, 22, 26...Z stage, 28...processing section, 28A...processing unit, 28B...optical unit, 30...inspection section, 30A...inspection unit, 30B...optical unit, 50...control device, 52...input / output section, 54-1, 54-2...X drive section, 56-1, 56-2...θ drive section, 58...vibration suppression mechanism, 60, 64...Y drive section, 62, 66...Z drive section, C1, C2...wafer chuck, CW1 to CW4...counterweight, G1 to G4...guide rail

Claims

1. A plurality of stages configured to be movable independently of each other in a first direction, the plurality of stages including a first stage and a second stage arranged side by side in a second direction orthogonal to the first direction, at least one counterweight configured to be movable in the first direction, counterweight control means for moving the at least one counterweight so as to suppress vibrations generated by the movement of at least any one of the plurality of stages, wherein the at least one counterweight includes a first counterweight arranged on the side opposite to the side where the second stage of the first stage is arranged, and a second counterweight arranged on the side opposite to the side where the first stage of the second stage is arranged, wherein the counterweight control means moves the at least one counterweight in a direction opposite to the moving direction of the first stage or the second stage, a processing apparatus.

2. A plurality of stages configured to be movable independently of each other in a first direction, the plurality of stages including a first stage and a second stage arranged side by side in a second direction orthogonal to the first direction, at least one counterweight configured to be movable in the first direction, counterweight control means for moving the at least one counterweight so as to suppress vibrations generated by the movement of at least any one of the plurality of stages, wherein the at least one counterweight includes a third counterweight arranged between the first stage and the second stage, wherein the counterweight control means moves the at least one counterweight in a direction opposite to the moving direction of the first stage or the second stage, a processing apparatus.

3. A plurality of stages configured to be movable independently of each other in a first direction, the plurality of stages including a first stage and a second stage arranged side by side in a second direction orthogonal to the first direction, at least one counterweight configured to be movable in the first direction, counterweight control means for moving the at least one counterweight so as to suppress vibrations generated by the movement of at least any one of the plurality of stages, The at least one counterweight includes a pair of first-stage-side counterweights disposed on both sides of the first stage and a pair of second-stage-side counterweights disposed on both sides of the second stage. The counterweight control means is a processing apparatus that moves the at least one counterweight in a direction opposite to the moving direction of the first stage or the second stage.

4. A processing method using a plurality of stages that are each independently movable in a first direction and include a first stage and a second stage arranged side by side in a second direction orthogonal to the first direction, including a step of moving at least one counterweight so as to suppress vibrations generated by the movement of at least any one of the plurality of stages, the at least one counterweight includes a first counterweight disposed on a side opposite to the side where the second stage of the first stage is disposed, and a second counterweight disposed on a side opposite to the side where the first stage of the second stage is disposed, the step of moving the counterweight is a processing method that moves the at least one counterweight in a direction opposite to the moving direction of the first stage or the second stage.

5. A processing method using a plurality of stages that are each independently movable in a first direction and include a first stage and a second stage arranged side by side in a second direction orthogonal to the first direction, including a step of moving at least one counterweight so as to suppress vibrations generated by the movement of at least any one of the plurality of stages, the at least one counterweight includes a third counterweight disposed between the first stage and the second stage, the step of moving the counterweight is a processing method that moves the at least one counterweight in a direction opposite to the moving direction of the first stage or the second stage.

6. A processing method using a plurality of stages that are each independently movable in a first direction and include a first stage and a second stage arranged side by side in a second direction orthogonal to the first direction, including a step of moving at least one counterweight so as to suppress vibrations generated by the movement of at least any one of the plurality of stages, the at least one counterweight includes a pair of first stage side counterweights disposed on both sides of the first stage and a pair of second stage side counterweights disposed on both sides of the second stage, the step of moving the counterweight is a processing method of moving the at least one counterweight in a direction opposite to the moving direction of the first stage or the second stage.

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